Hydrostatic transmissions are seeing wider and wider application, in numerous systems :- from ride on lawn mowers, to their application in lower cost 4 x 4 automotive vehicles & off highway wquipment.
But there has been a recurring issue with Hydrostatic systems since their initial conception & development… in that:-
The main fluid circuit has no filtration,
This is because the fluid flows both ways in the main loop (bi-directional), as the system is used to drive the vehicle both forward and back.
It is not possible to use conventional filtration in a high pressure, bi-directional circuit, without two high pressure filter housings being employed, coupled with two non return valves, resulting in a very expensive, very large and restrictive installation, which is why it is extremely rare to find such a solution in anything but very large-high value hydrostatic applications.
Without the benefit of a filter/separator in the main hydrostatic circuit/loop, contamination generated within the system reaches higher and higher concentrations, until the pump, motors and valves catastrophically fail, as a direct result of the increasing exposure to increasing levels of generated contaminant.
Previously the only filtration typically fitted to Hydrostatic systems, is on the top up line, which only sees a small amount of fluid & contamination, when the system tops up any losses.
Until now, there has been no way to address this issue… but with the Magnom CPU (Circuit Protection Unit) products, it is now possible and viable to maintain the fluid cleanliness in a high pressure hydrostatic main loop/circuit, with fluid flowing in both directions (Bi-Directional) without restriction to fluid flow!
Consider the issue its self:-
The majority of contamination found in say a hydrostatic transmission is ‘Steel and/or Iron’
Typically built into the system during manufacture, generated during break/run in, and through general wear and tear.
This Fe contamination, free to circulate around the Hydrostatic loop, also generates Bronze, Aluminium etc, as well as even more Fe, “The Chain Reaction of Wear”
“The worse things get – The faster things get worse”
The Fe is typically sub 15 micron in size (most sub 10 micron), so even if you could employ a conventional filter in these systems, they would not be very effective, and/or be very restrictive to flow.
The Magnom CPU range (Circuit protection Unit) was developed for just such applications,
Magnpm CPU product range
Available in Alloy or Stainless steel housings, with working pressures of up-to 6000 psi (tested up to 24,000 psi),
Independent testing in hydraulic and lube systems has seen high efficiency results in ‘Single Pass’ testing (conventional filtration is multi-pass rated).
Removing contaminants down to sub micron levels, with up-to 99.97% efficiency ‘Single pass’ at 10 microns.
The CPU’s are Bi-directional, and do not suffer from wash off of contaminant, they also remain transparent to fluid flow, (non restrictive) even when full of collected contaminant.
They are generally available in SAE sizes from -12 to -16.
One customer described the Magnom products as “The cure for death of a transmission system”
We have yet to see any other filter/separator that can be used in these systems…
The CPU products are standard production units on many OEM applications, they are a fraction of the size of conventional filtration, and size for size offer a far greater contaminant capacity.
In some applications Magnom units are a “Fit and Forget” proposition for the user.
Our challenge is… Try one, You will not believe it until you witness it for yourself.